1. Field of the Invention
The invention relates to printers for continuously marking extruded plastic products, and more specifically, to rotary printers which use heat, pressure, and film-backed marking tape to apply an embedded mark in plastic pipe.
2. Prior Art
In the past, rotary hot-foil leaf/brander marking machines have been developed to be installed directly between sizing and take-off equipment on an extrusion line. These friction-driven marking systems for smooth plastic pipe use a marking wheel into the periphery of which individual type of numerals and/ or letters may be set. The wheel is rotated by means of contact with the moving pipe to imprint the pipe, and specifically to press portions of a foil tape into the surface of the pipe. Unfortunately, such devices require a great deal of set-up time to set the individual type in the periphery of the marking wheel and to fixture the marking wheel relative to the surface of a pipe fixed diameter. The type and the position of the marking wheel are incapable of being changed during an extrusion run.
The subject invention overcomes these disadvantages by providing a device that is easily adjustable for different printed indicia, pipe sizes and variations of printed indicia during a continuous extrusion run.